Taxonomic Notes
There are no significant taxonomic issues associated with this name.
Justification
Eryngium viviparum is listed as Endangered due to its highly restricted area of occupancy, of less than 80 km² (the real area of occupancy in France is 1 km², while a conservative estimate for the Spanish populations is 72 km²). It has more than ten locations, but is now considered as severely fragmented, as numerous subpopulations have been lost. The extent of occurrence, the area of occupancy, the number of locations and of sub-populations, quality of habitat, as well as the number of individuals has drastically decreased in the last ten years, becoming reduced to a single population in France, 16-18 populations in Spain and one current population in Portugal. Around 35% of the Spanish subpopulations and 50% of the French sub-populations disappeared in the last ten years.
Geographic Range Information
Eryngium viviparum is native to France, Spain and Portugal. In France, it is only found in Morbihan at a small site of 1 km². In Spain, it is present in Galicia and Castilla y León. It occured in the north of Portugal, however the populations in Portugal are considered to be extinct (Reduron 2007). Therefore, the estimated area of occupancy may be 80 km².
Population Information
The species has undergone a very strong decline over an already small area. Only a few localities remain in the world. The decline has been spectacular in Bretagne, where the plant was abundant 50 years ago with around 50 sites in Brittany between 1975 and 1980 (Half of the localities have been lost in the last 10 years). Populations at Séné et de Saint Philbert have apparently disappeared, and the species has not been seen since at most others. There is now only a single confirmed site in France, with 200-1,500 individuals depending on the year. Although this number may appear high, wetland degradation can lead to the rapid loss of a large number of plants (Reduron 2007). In the Iberian Peninsula, 93% of the population occurs in northwest Spain with 20 subpopulations (eight additional localities have disappeared in recent years), with over 15,000 individuals, mainly in Galicia as a very scattered population; 57% of the population is considered to be threatened and approximately 2% is on the verge of extinction. In Portugal, the population at the locus classicus in Portugal is considered to be extinct, but a new small population has been discovered in the Serra da Nogueira (Reduron 2007, ICN 2006). This population is small with a very low number of individuals and also faces a high risk of extinction (ICN 2006).
Habitat and Ecology Information
The natural habitat of E. viviparum comprises acid depressions in the Atlantic heaths, where it is a pioneer species, intolerant of competition. These sites are generally exploited as winter-inundated pastures, where poaching by cattle enables the plant to survive. In Brittany, the soil is derived from granite (granulite) which results in grey clays irregularly blue or iron-stained, brown soils with elements of quartz and upper organic horizons; such soils tends to retreat in times of drought; their pH is around 6.5. The species colonized temporarily submerged soils, dry during the summer.
This plant grows in the following Habitats Directive listed habitats (Commission of the European Communities 2009):
- 3110 Oligotrophic waters containing very few minerals of sandy plains (Littorelletalia uniflorae)
- 3130 Oligotrophic to mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or of the Isoëto-Nanojuncetea
- 6410 Molinia meadows on calcareous, peaty or clayey-silt-laden soils (Molinion caeruleae)
Threats Information
Pools supporting this species tend to disappear due to natural succession of the habitat (invasion by Molinia) and due to a variety of anthropogenic modification and degradation of the habitat; such as drainage and cultivation of maize, conifer plantation, urbanisation, disposal of organic wastes and decline in grazing. Sand extraction is also problematic in some part of its range.
Use and Trade Information
This species is not used.
Conservation Actions Information
This taxon is listed as priority species on Annexes II and IV of the Habitats Directive and under Appendix I of the Convention on the Conservation of European Wildlife and Natural Habitats (Bern Convention). In France, it is protected at national level (Annex I). In Spain, it is included as species with “Protección Especial” in the national list of species in regime of special protection of Spain, and protected at regional level in Galicia and in Castilla y León. It is listed as Endangered on the Spanish Red List (Moreno 2008) and on the French Red List (Olivier et al. 1995). In France, there is a Species Recovery Action Plan from the CBN of Brest to reinforce the last locality and to search for seeds and plantlets in the soil of the previous localities. If this fails, some cultivated individuals might be reintroduced in the previous localities. One locality occurs in a protected area in France, others are included in national parks in Spain.
The creation of micro-reserves, the monitoring and restoration of the habitat and the translocation of some individuals are the recommended conservation measures.